The ses light flashes when you have a catalytic converter damaging event. Most commonly a missfire. You really need some form of code reading. Running 14 psi on a regular basis, You an that ses light are gonna be seeing each other often. Good luck.

 

Checking the plugs is MANDATORY at this point. They can tell you alot

 

When my cats started to go, I noticed a progressive deterioration in performance. It was when I was N/A as a "miss fire" in the upper rpms. Then it progressed over the course of a week to the point where I'd rev the engine and when the throttle blade would shut it would build positive manifold pressure. Anytime you dump unburnt fuel into the cats from a big cam with lots of overlap or from an excessively rich condition they break down. It's any easy thing to check to help you eliminate variables.

 

LMAO thought that was fun, but it is all too true

 

sounds like the 5.3 #7 stricks again......... Welcome to the club (maybe).........

 

Glad I didnt buy a Procharger. lol

 

about a month ago mine started flashing and it was missfireing bad. pulled the plugs and all four on the pass side were fouled out. eneded up being a bad O2 sensor. like the others said you wont know till you read the codes.

 

LMAO!

 

check those plugs and gap from .30-.35 to be honest sounds like its mr. #7 again good luck. check the codes and let us kno what happins!!!!

 

Well, I went to MTI and it took them about 5 minutes to tell me for sure that I KO'ed the #7 piston. Just went out and bought a cummins so I would have something to drive.

Coming Soon: 408, stage 2r ls1 heads from MTI, custom cam from MTI, Meth, race fuel, and more boost.

Engine only lasted 2 days. I bet the trans only last 2 days next time.